In recent years, a display element of an image display device such as a television receiver is shifting from a conventional CRT display device to a thin display device using a thin display element such as a liquid crystal panel and a plasma display panel. This enables the image display device to have a reduced thickness. A liquid crystal panel used for a liquid crystal display device does not emit light, and thus a backlight unit is required as a separate lighting device.
As the backlight unit, a direct type backlight unit that supplies light directly to a liquid crystal panel from the rear side of the liquid crystal panel is known. In such a backlight unit, a reflection sheet may be provided on a light source board on which light sources such as LEDs are arranged.
Patent Document 1 discloses a direct type backlight unit including the reflection sheet provided on the light source board on which LEDs are arranged. The backlight unit includes LEDs, an LED board on which the LEDs are arranged, a diffuser plate arranged to face light emitting surfaces of the LEDs, spacers arranged on the LED board, and a reflection sheet arranged on the LED board. The reflection sheet has a plurality of through holes through which the light sources and the spacers are passed. In this backlight unit, the spacers maintain a predetermined distance between the LED board and the diffuser plate, and thus uneven brightness of a display surface of the backlight unit can be prevented or suppressed.    Patent Document 1: Japanese Unexamined Patent Publication No. 2010-15853